Abstract

We apply the methodology of self-consistent Brownian dynamics simulations to study the self-assembly behavior in melts of semiflexible-flexible diblock copolymers as a function of the persistence length of the semiflexible block. Our results reveal a novel progression of morphologies in transitioning from the case of flexible-coil to rod-coil copolymers. At even moderate persistence lengths, the morphologies in the semiflexible-block rich region of the phase diagram transform to liquid crystalline phases. In contrast, the phases in the flexible-block rich region of the phase diagram persist up to much larger persistence lengths. Our analysis suggests that the development of orientational order in the semiflexible block to be a critical factor influencing the morphologies of self-assembly.

Received 13 January 2012Accepted 19 February 2012Published online 08 March 2012

Acknowledgments:

This work was supported as a part of an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award No. DE-SC0001091. Parts of this work were also by grants from Robert A. Welch Foundation (Grant No. F1599) and National Science Foundation (Grant No. DMR 1005739). The authors acknowledge the Texas Advanced Computing Center (TACC) for computing resources.

Abstract

We apply the methodology of self-consistent Brownian dynamics simulations to study the self-assembly behavior in melts of semiflexible-flexible diblock copolymers as a function of the persistence length of the semiflexible block. Our results reveal a novel progression of morphologies in transitioning from the case of flexible-coil to rod-coil copolymers. At even moderate persistence lengths, the morphologies in the semiflexible-block rich region of the phase diagram transform to liquid crystalline phases. In contrast, the phases in the flexible-block rich region of the phase diagram persist up to much larger persistence lengths. Our analysis suggests that the development of orientational order in the semiflexible block to be a critical factor influencing the morphologies of self-assembly.